An idea I had a while ago and just remembered. Basically, what I am envisioning is some sort of program that parses a text and attempts to determine certain information about it. For example it could catagorize different genres, "horror", "romance", "technical", "philosophy", so on. It could also attempt to discern information like when a text was written "early 1800s" vs. "2000s", or whether the author is male or female, or multiple authors.

I doubt there would be any practical purpose for such a thing, but I figure it would be an interesting novelty.

Does anything like this already exist? If so, where can I learn more about it?